University of Zurich, Institute for Empirical Research in Economics, Blumlisalpstrasse 10, CH-8006 Zurich, Switzerland.

....In the absence of trust among trading partners, market transactions break down. In the absence of trust in a country's institutions and leaders, political legitimacy breaks down. Much recent evidence indicates that trust contributes to economic, political and social success. Little is known, however, about the biological basis of trust among humans. Here we show that intranasal administration of oxytocin, a neuropeptide that plays a key role in social attachment and affiliation in non-human mammals, causes a substantial increase in trust among humans, thereby greatly increasing the benefits from social interactions. We also show that the effect of oxytocin on trust is not due to a general increase in the readiness to bear risks. On the contrary, oxytocin specifically affects an individual's willingness to accept social risks arising through interpersonal interactions. These results concur with animal research suggesting an essential role for oxytocin as a biological basis of prosocial approach behaviour...

then if you read the paper, where the experiment involved partipants as investors and trustees to increase personal wealth, it also continues:

....oxytocin promotes prosocial approach behaviour by inhibiting defensive behaviours, but there is no evidence that oxytocin affects reciprocity in animals...

link is below, need to go in through lib pubmed though, or can get from me:

www.nature.com.libproxy1.nus.edu.sg/nature/journal/v435/n7042/full/nature03701.html

At the rate they are deconstructing all our human emotions and drives, I wonder what kind of therapies or drugs we will have in the future. What exactly do they eventually hope to achieve with this study?

Maybe.... I know...

World peace! hoorah.